U.S. patent application number 16/206486 was filed with the patent office on 2019-03-28 for respiration device and method for a respiration device.
The applicant listed for this patent is Loewenstein Medical Technology S.A.. Invention is credited to Benno DOEMER, Dominic KLAUSMANN.
Application Number | 20190091427 16/206486 |
Document ID | / |
Family ID | 53546492 |
Filed Date | 2019-03-28 |
United States Patent
Application |
20190091427 |
Kind Code |
A1 |
DOEMER; Benno ; et
al. |
March 28, 2019 |
RESPIRATION DEVICE AND METHOD FOR A RESPIRATION DEVICE
Abstract
The present invention relates to a method and a respiration
device having a respiration unit for generating an airflow for the
respiration and having a monitoring unit. The monitoring unit is
used to detect a respiration parameter and to classify events in
the respiration on the basis of monitoring of the respiration
parameter. In this case, the monitoring unit is configured to carry
out an event analysis to recognize an occurrence, which is
characteristic for Cheyne-Stokes respiration, of chronologically
successive events and for this purpose to ascertain the period
length thereof and to compare them to one another and to register
the presence of Cheyne-Stokes respiration when the compared period
lengths each deviate by less than 40% from one another.
Inventors: |
DOEMER; Benno; (Ettlingen,
DE) ; KLAUSMANN; Dominic; (Freiburg, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Loewenstein Medical Technology S.A. |
Luxembourg |
|
LU |
|
|
Family ID: |
53546492 |
Appl. No.: |
16/206486 |
Filed: |
November 30, 2018 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
14834686 |
Aug 25, 2015 |
10159810 |
|
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16206486 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 2016/0036 20130101;
A61M 2230/10 20130101; A61M 16/024 20170801; A61M 2230/04 20130101;
A61M 2230/205 20130101; A61B 5/4818 20130101; A61M 2230/42
20130101; A61M 16/208 20130101; A61M 2230/60 20130101; G16H 40/63
20180101; A61M 16/16 20130101; A61M 16/0051 20130101; G16H 50/20
20180101; A61M 2016/0027 20130101; A61B 5/7264 20130101; A61M
2230/205 20130101; A61B 5/0816 20130101; A61M 2205/50 20130101;
A61B 5/0826 20130101; A61M 16/0069 20140204; A61M 2230/14 20130101;
A61M 2230/005 20130101; A61M 2230/005 20130101; A61M 2230/42
20130101 |
International
Class: |
A61M 16/00 20060101
A61M016/00; G16H 40/63 20180101 G16H040/63; G16H 50/20 20180101
G16H050/20; A61B 5/08 20060101 A61B005/08; A61B 5/00 20060101
A61B005/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 28, 2014 |
DE |
102014012791.5 |
Claims
1. A respiration device, wherein the device comprises at least one
respiration unit for generating an airflow for respiration and at
least one monitoring unit for detecting at least one respiration
parameter and for classifying events in the respiration on the
basis of monitoring the at least one respiration parameter, the
monitoring unit being configured to monitor at least one flow
signal and/or at least one pressure signal from at least one
associated sensor unit to detect at least one flow property and/or
at least one pressure property of an airflow for the respiration
and to analyze it on the basis of at least one algorithm in order
to classify an event, and further being configured to sort events
into at least two relevance classes, comprising at least one first
relevance class comprising events which are relevant for CS
(Cheyne-Stokes) respiration and at least one second relevance class
comprising events which are irrelevant for CS respiration.
2. The respiration device of claim 1, wherein the first relevance
class comprises at least events of a hyperventilation and/or a
hypoventilation and/or a hypopnea and/or an apnea and/or the second
relevance class comprises at least events of inspiration,
expiration, snoring, swallowing, speaking, nose blowing, and/or
coughing, and/or a respiration interruption and/or a leak.
3. The respiration device of claim 1, wherein the monitoring unit
is configured to sort the events of the first relevance class into
at least two validity classes for the event analysis, comprising a
first validity class comprising events which typically occur in the
case of CS respiration and a second validity class comprising
events which typically do not occur in the case of CS
respiration.
4. The respiration device of claim 3, wherein the first validity
class comprises at least events of a central apnea and/or a central
hypopnea.
5. The respiration device of claim 3, wherein the second validity
class comprises at least events of an obstructive apnea and/or an
obstructive hypopnea.
6. The respiration device of claim 2, wherein the monitoring unit
is configured to register the presence of CS respiration when at
least three events occur in chronological succession and in this
case at least two of the at least three events correspond to the
first validity class and at most one event of the at least three
events corresponds to the second validity class.
7. The respiration device of claim 6, wherein at least four events
are analyzed.
8. The respiration device of claim 1, wherein the device is
configured to output a corresponding notification to a user in the
event of registered CS respiration.
9. The respiration device of claim 1, wherein the device is
configured, in the event of registered CS respiration, to set the
respiration unit to at least one respiration mode for respiration
in the case of CS respiration.
10. The respiration device of claim 1, wherein the the monitoring
unit is configured to carry out at least one event analysis to
recognize an occurrence of chronologically successive events which
is characteristic CS respiration, to ascertain respiration
amplitudes for at least three chronologically successive
respiration events for this purpose (inspiration and expiration),
and to compare the ascertained respiration amplitudes at least
partially to one another and to register a presence of CS
respiration when the compared respiration amplitudes deviate by at
least 25% from one another.
11. The respiration device of claim 1, wherein ascertainment,
storage, and display of an amplitude strength of the CS
respiration, consisting of hypopneas versus apneas, are
performed.
12. The respiration device of claim 1, wherein recognized CS
respiration is confirmed or discarded by analysis of pulse oximeter
signals.
13. The respiration device of claim 12, wherein pulse frequency or
pulse wave amplitude or pulse transit time (PTT) are used as pulse
oximeter signals.
14. The respiration device of claim 12, wherein the pulse oximeter
is connected to the respiration device via an interface, to be able
to record data in a time-correlated manner.
15. The respiration device of claim 1, wherein the monitoring unit
uses a value of a period length between events as a further
indication of a presence of CS respiration.
16. The respiration device of claim 15, wherein presence of CS
respiration is presumed when period lengths are each at least 40
seconds and at most 90 seconds.
17. The respiration device of claim 3, wherein the monitoring unit
considers a number of events sorted into the first and the second
validity classes together with a total number of all events
considered in an event analysis in the sense of a conclusiveness
test.
18. The respiration device of claim 3, wherein a differentiation
between a central apnea, classified as a valid event, and an
invalid obstructive apnea is carried out by the monitoring unit on
the basis of an analysis of the at least one flow signal and the at
least one pressure signal.
19. The respiration device of claim 18, wherein a beginning of an
apnea is recognized on the basis of a flow variation and an end of
the apnea is recognized on the basis of a pressure variation and/or
a flow variation.
20. The respiration device of claim 19, wherein obstructive apnea
is detected by an occurrence of a short, additional pressure
increase at the end of the apnea.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of U.S. patent
application Ser. No. 14/834,686, filed Aug. 25, 2015, which claims
priority under 35 U.S.C. .sctn. 119 of German Patent Application
No. 10 2014 012 791.5, filed Aug. 28, 2014. The entire disclosures
of these applications are expressly incorporated by reference
herein.
BACKGROUND OF THE INVENTION
Field of the Invention
[0002] The present invention relates to a method for operating a
respiration device and a respiration device having at least one
respiration unit for generating an airflow for respiration and
having at least one monitoring unit. The monitoring unit is used to
detect at least one respiration parameter and to classify events in
the respiration on the basis of monitoring of the respiration
parameter.
2. Discussion of Background Information
[0003] In the case of respiration devices, it is often advantageous
if the possibility exists for recognizing respiratory disturbances
during respiration. On the one hand, this enables monitoring of the
efficiency of the respiration and, on the other hand, primary and
secondary illnesses can be recognized better.
[0004] One form of such a respiratory disturbance is so-called
Cheyne-Stokes respiration (CS respiration). CS respiration is
frequently induced by defective respiratory regulation. The trigger
or primary illness in this case is frequently cardiac
insufficiency. CS respiration is characterized by alternating
phases, which merge softly into one another, of hypoventilation
(hypopnea and apnea) and hyperventilation. A relatively brief
respiratory arrest can frequently also follow the shallowest
breaths. The breaths then increasingly deepen thereafter.
[0005] An array of methods and devices are known in the prior art,
which enable recognition of CS respiration during respiration. For
example, EP 1 867 227 A2 describes CS recognition on the basis of a
peak in the spectrogram, the flow, and apnea/hypopnea recognition.
In addition, the measure is used for the steepness of the rebound
of the respiration after hypoventilation. EP 2 421 435 A1
recognizes CS respiration on the basis of an oximeter signal via
the length and the rebound of the saturation. WO 2013/110 136
recognizes CS respiration on the basis of a graph of the cycle
lengths, which are used in the course of event recognition. CS
recognition is performed in WO 2009/118 737 by means of
determination of the start and end of apneas, calculation of time
offsets between the apneas, and subsequent generation of an output
on the basis of the multiple of the cycle lengths. The entire
disclosures of the documents mentioned above are incorporated by
reference herein.
[0006] In view of the foregoing, it would be advantageous to have
available a respiration device and a method for operating a
respiration device which enable reliable and uncomplicated
recognition of CS respiration.
SUMMARY OF THE INVENTION
[0007] The present invention provides a respiration device and a
method for a respiration device as set forth in the instant
independent claims. Several advantages and features of the present
invention result from the dependent claims. Further advantages and
features are specified in the general description and the
description of the exemplary embodiment.
[0008] The respiration device according to the invention comprises
at least one respiration unit for generating an airflow for
respiration and at least one monitoring unit. The monitoring unit
is used to detect at least one respiration parameter and to
classify events in the respiration on the basis of monitoring of
the respiration parameter. In this case, the monitoring unit is
able and designed to carry out at least one event analysis to
recognize chronologically successive events. The event analysis is
used in this case to recognize an occurrence of the events which is
characteristic for CS respiration. For the event analysis, the
monitoring unit is able and designed to ascertain period lengths
between the events. In addition, the monitoring unit is able and
designed to compare the ascertained period lengths at least
partially to one another. The monitoring unit is additionally also
able and designed to register the presence of CS respiration when
the comparison of the period lengths has the result that the
compared period lengths deviate from one another by less than
40%.
[0009] The respiration device according to the invention has many
advantages. One substantial advantage is that a monitoring unit is
provided, using which a characteristic occurrence of
chronologically successive events is used to recognize CS
respiration. The monitoring unit identifies the characteristic
occurrence in this case on the basis of a comparison of the period
lengths between the events and a corresponding evaluation of the
deviation of specific period lengths from one another. Such a
recognition of the CS respiration is very reliable, since the
periodicity of specific events is an essential feature of CS
respiration.
[0010] In addition, such a monitoring unit, which carries out an
event analysis to recognize CS respiration, can be implemented in a
comparatively uncomplicated manner. Many devices already have the
capability of detecting events in respiration and recognizing them
as specific types. The classified events can then be used as the
foundation for the CS recognition.
[0011] In particular, a characteristic occurrence of at least two
and preferably three chronologically successive events is used to
recognize CS respiration. The period lengths of adjacent events are
preferably compared to one another. In this case, CS respiration is
registered when the period lengths between adjacent events deviate
from one another by less than 40% and preferably less than 30% and
particularly preferably less than 20%. In this case, events, which
in particular are not considered for the ascertainment and the
comparison of the period lengths, can also lie between the adjacent
events.
[0012] In one advantageous refinement, the monitoring unit is able
and designed to carry out at least one event analysis for
recognizing an occurrence of at least three chronologically
successive events which is characteristic for Cheyne-Stokes
respiration and for this purpose to ascertain at least one first
period length between a first event and a second event and one
second period length between a second event and a third event and
to at least partially compare them to one another and to register
the presence of Cheyne-Stokes respiration when the first period
length and the second period length deviate from one another by
less than 40%.
[0013] The monitoring unit is preferably able and designed to carry
out at least one event analysis of at least four chronologically
successive events. The event analysis is used in this case to
recognize an occurrence of the four events which is characteristic
for CS respiration. For the event analysis, the monitoring unit is
able and designed to ascertain at least one first period length
between a first event and a second event and one second period
length between a second event and a third event and one third
period length between a third event and a fourth event. In
addition, the monitoring unit is able and designed to compare the
ascertained period lengths at least partially to one another. The
monitoring unit is additionally able and designed to register the
presence of CS respiration when the comparison of the period
lengths has the result that the first period length and the second
period length deviate from one another by less than 40% and the
second period length and the third period length deviate from one
another by less than 40%.
[0014] One advantage in this case is that a monitoring unit is
provided, using which a characteristic occurrence of at least four
chronologically successive events is used to recognize CS
respiration. The error threshold is thus significantly
improved.
[0015] It is also particularly advantageous for recognizing CS
respiration that the monitoring unit separately checks the
prescribed deviation of at most 40% in each case for two adjacent
period lengths. By way of the determination of the relative
deviation of the period lengths from one another, substantially
more reliable recognition of CS respiration is possible than, for
example, with monitoring of an absolute deviation of the period
lengths. Although CS respiration is generally distinguished by a
similar period length of adjacent events, the period length can
nonetheless increase or decrease more strongly over multiple
events. This context is taken into account by the consideration of
a relative deviation of adjacent events, and the reliability of the
CS recognition is increased.
[0016] It is also possible that the third period length is
ascertained without the fourth event. This is performed, for
example, by recognizing a combined hyper-hypoventilation event,
wherein the third period length then corresponds to the event
length. Other methods, e.g. statistical evaluations of event
sequences, are also possible. The fourth period length is
preferably also compared to the third period length, so that CS
respiration can be established on the basis of the amount of the
deviation from one another.
[0017] The event analysis can also comprise at least one fifth or
one sixth event. The event analysis can also comprise a plurality
of events. It is also possible that a large part of the events or
also all events during the respiration are used for the event
analysis. In this case, the comparison of the period lengths of
adjacent events can be continued in the corresponding sequence. The
analysis of the events can also be repeated one time or multiple
times or progressively after the four events or a specific number
of events, however.
[0018] In the meaning of this invention, the term period length
means in particular the time between two comparable points in time
within two events. For example, the period length can extend from a
beginning or an end or a middle of one event to the beginning or
the end or the middle of another event. It is also possible that an
event may be described on the basis of a function. The period
length then preferably extends from one defined value of the
function of an event to another defined value of the function of an
adjacent event. For example, the period length extends from a
maximum of one event to a maximum of the adjacent event.
[0019] In a preferred embodiment, the monitoring unit is able and
designed to register the presence of CS respiration when the first
period length and the second period length and also the second
period length and the third period length each deviate from one
another by less than 35%. The monitoring unit particularly
preferably registers CS respiration when the first period length
and the second period length and also the second period length and
the third period length each deviate from one another by less than
30%. A lesser deviation than the limiting value is possible, for
example, 20% or less.
[0020] The period lengths preferably extend between a chronological
middle of one event and a chronological middle of a following
event. In particular, the monitoring unit is able and designed to
calculate the period lengths starting from a chronological middle
of the event. In this case, the monitoring unit is in particular
able and designed to also determine the beginning and/or the end of
an event. For this purpose, chronological changes of the detected
respiration parameter are used in particular, which are
characteristic for the beginning and/or the middle and/or the end
of an event.
[0021] It is preferable for the monitoring unit to be able and
designed to sort the events for the event analysis into at least
two relevance classes. The two relevance classes comprise in this
case in particular at least one first relevance class having events
which are relevant for CS respiration. The first relevance class
can also comprise events which can be used as positive features
and/or negative features for the presence of CS respiration.
[0022] In particular, the two relevance classes comprise at least
one second relevance class having events which are irrelevant for
CS respiration. Further relevance classes having another weighting
of the events can be provided.
[0023] Such a sorting of events has the advantage that the further
event analysis can be performed more efficiently and substantially
less complexly, since, for example, irrelevant events do not have
to be analyzed further.
[0024] The sorting into the second relevance class can also be
performed indirectly in the meaning of non-assignment to the first
relevance class. The monitoring unit is preferably able and
designed to carry out the sorting into the relevance classes before
the determination of the period length. In particular, only the
events of the first relevance class are subjected to the event
analysis, if the sorting into the relevance classes is not included
in the event analysis.
[0025] The monitoring unit is preferably able and designed to
consider a previously performed classification of the events during
the sorting into the relevance classes. Thus, for example, sorting
can be performed depending on the event type.
[0026] In particular, the first relevance class comprises at least
the events of a hyperventilation and/or a hypoventilation and/or a
hypopnea and/or an apnea.
[0027] The second relevance class comprises in particular at least
the events of inspiration, expiration, snoring, swallowing,
speaking, nose blowing, and/or coughing, and/or a respiration
interruption and/or a leak in the respiration system.
[0028] In one advantageous refinement, the monitoring unit is able
and designed to sort the events of the first relevance class into
at least two validity classes for the event analysis. The two
validity classes preferably comprise a first validity class and a
second validity class. The first validity class comprises in
particular events which typically occur during CS respiration. The
second validity class comprises in particular events which
typically do not occur during CS respiration.
[0029] The first validity class comprises in particular events
which can be used as positive features for the presence of CS
respiration. The events of the second validity class can be events
which indicate that CS respiration is currently not present. Such a
sorting of the events into at least two validity classes simplifies
the assessment of whether or not CS respiration is present.
[0030] The first validity class preferably comprises at least the
events of a central apnea and/or a central hypopnea.
[0031] The second validity class preferably at least comprises the
events of an obstructive apnea and/or an obstructive hypopnea.
[0032] The monitoring unit is particularly preferably able and
designed to register the presence of CS respiration when at least
three analyzed events and in particular three of the at least four
analyzed events are chronologically successive and fulfill at least
two conditions. The first condition is that at least two of the at
least three events correspond to the first validity class. The
second condition is that at most one event of the at least three
events corresponds to the second validity class. Further conditions
are possible, which regulate in particular the occurrence of
specific types of events. Such an embodiment has the advantage that
the monitoring unit can reliably register the presence of CS
respiration by means of an assessment of positive and negative
features. In particular, the three events are directly
chronologically successive. In this case, at least one event, which
is not considered for the event analysis, can lie between the
directly following events.
[0033] In a further preferred embodiment, the monitoring unit is
able and designed to register the presence of CS respiration if a
first and a second and a third period length each last at least 35
seconds and preferably at least 40 seconds. The first and the
second and the third period length preferably each last at least 35
seconds and preferably at least 40 seconds. The monitoring unit is
also particularly preferably able and designed to register the
presence of CS respiration if the first and the second and the
third period length each last at most 95 seconds and preferably at
most 90 seconds. Since CS respiration is generally characterized by
events occurring in specific time intervals, limiting of the period
length is particularly advantageous for recognizing CS respiration.
At least one of the period lengths can also be determined by a
statistical method or by using at least one event length.
[0034] It is possible and preferable for the monitoring unit to be
able and designed to register the presence of CS respiration when a
chronological duration of each one of the events taken into
consideration for the event analysis is at most 80% of the period
length, in particular when a chronological duration of each one of
the at least four events is at most 80% of the period length. In
particular, the CS respiration is registered when the chronological
duration of the individual events is in each case at most 70% of
the period length. The limiting value can also be less, for
example, 60% or 50% or less. By way of such an embodiment, the
durations of the individual events are set in a relation to the
event-free time between the events, which is well suitable for
recognizing CS respiration.
[0035] It is possible that the monitoring unit is able and designed
to monitor a flow signal and/or a pressure signal and to analyze
them on the basis of at least one algorithm, in order to classify
an event. The flow signal and/or the pressure signal are provided
in this case by at least one sensor unit, which is associated with
the monitoring unit. The sensor unit is provided in this case for
detecting at least one flow property and/or at least one pressure
property of the airflow for the respiration. The analysis of flow
signals or pressure signals enables reliable recognition and
classification of events of the respiration.
[0036] The monitoring unit is also particularly preferably able and
designed to register at least one respiration parameter, for
example, the respiration frequency, the breath volume, the
respiratory minute volume, the inspiration flow and/or the
inspiration pressure and/or the airway resistance, on the basis of
the flow signal and/or the pressure signal.
[0037] The monitoring unit can be able and designed to output a
corresponding notification to a user in the event of registered CS
respiration. For example, the notification can be visually and/or
acoustically displayed by means of a display unit. The notification
can also be output, for example, by means of an interface to at
least one external data processing unit. Such a notification is
particularly advantageous, since the respiration treatment can be
adapted accordingly in awareness of the CS respiration. On the
other hand, if the notification does not appear, corresponding
success of the respiration treatment can be established.
[0038] The monitoring unit is alternatively also able and designed,
in the event of registered Cheyne-Stokes respiration, to set the
respiration unit to at least one respiration mode for respiration
in the case of Cheyne-Stokes respiration.
[0039] The monitoring unit can also be able and designed to, in the
event of registered CS respiration, output a corresponding
notification to a user and/or document the CS respiration in a
progressive recording of the respiration. For example, the
notification can be visually and/or acoustically displayed by means
of a display unit. The notification can also be output, for
example, by means of an interface to at least one external data
processing unit. Such a notification and/or storage of the
registered CS respiration is particularly advantageous, since the
respiration treatment can be adapted appropriately in awareness of
the CS respiration. For example, an increase of the IPAP and/or an
increase of the EPAP is suppressed in the event of registered CS
respiration. Alternatively, a recommendation is output to reduce
the IPAP and/or the EPAP.
[0040] The monitoring unit is alternatively also able and designed
to, in the event of registered Cheyne-Stokes respiration, set the
respiration unit to at least one respiration mode for respiration
in the event of Cheyne-Stokes respiration, in which at least one
pressure (IPAP or EPAP) is reduced.
[0041] The monitoring unit can also be able and designed to, in the
event of registered CS respiration, consider it as a corresponding
respiratory disturbance in a respiration statistic. Such a
statistical analysis of the occurrence of CS respiration is helpful
to recognize primary illnesses, for example.
[0042] It can be provided that the monitoring unit is able and
designed to, in the event of registered CS respiration, set the
respiration unit to at least one respiration mode which is
optimized for respiration in the event of such CS respiration. Such
an embodiment has the advantage that the respiration unit is
automatically adapted when CS respiration is recognized. The user
thus immediately obtains respiration optimized for him. In
particular, the respiration mode, in the event of CS respiration,
comprises at least one adaptation of a respiration parameter and
preferably an anti-cyclic adaptation of the compression stroke. The
automatic setting of the respiration mode can be manually
deactivatable. The setting of the respiration mode is preferably
noted in the respiration statistic, so that a check can be
performed as to whether the changeover is advantageous for the
treatment.
[0043] The method according to the invention is used for operating
a respiration device having at least one respiration unit for
generating an airflow for respiration. The respiration device
comprises at least one monitoring unit for detecting at least one
respiration parameter and for classifying events in the respiration
on the basis of monitoring of the respiration parameter. In this
case, at least one occurrence of chronologically successive events,
which is characteristic for Cheyne-Stokes respiration, is
recognized on the basis of at least one event analysis. Period
lengths between the chronologically successive events are
ascertained for the event analysis.
[0044] The period lengths are at least partially compared to one
another. The presence of Cheyne-Stokes respiration is registered
when the compared period lengths deviate by less than 40% from one
another.
[0045] According to the invention, the monitoring unit is able and
designed to carry out at least one event analysis to recognize an
occurrence of chronologically successive events, which is
characteristic for Cheyne-Stokes respiration, and to ascertain
respiration amplitudes for at least three chronologically
successive respiration events for this purpose (inspiration and
expiration) and to compare the ascertained respiration amplitudes
at least partially to one another and to register the presence of
Cheyne-Stokes respiration when the compared respiration amplitudes
deviate by at least 25% from one another. In this case, the
amplitude is preferably determined from the flow or volume of
respiratory gas and results from the change of inflowing and
outflowing respiratory gas. For example, the first amplitude is
compared to the third amplitude, and CS respiration is recognized
when the first amplitude deviates by at least 25% from the third
amplitude. For example, the first amplitude is also compared to the
third amplitude, and CS respiration is recognized when the first
amplitude deviates by at least 50% from the third amplitude. CS
respiration is also recognized when the first amplitude deviates by
at least 75% from the third amplitude. For example, phases of at
least temporarily very low amplitude or absent amplitude can also
be displayed between the at least three chronologically successive
respiration events (inspiration and expiration) or within the three
respiration events. CS respiration is also recognized when phases
of at least temporarily very low amplitude or absent amplitude of
at least 8 seconds occur between the at least three chronologically
successive respiration events (inspiration and expiration) or
within the three respiration events.
[0046] According to the invention, ascertainment, storage, and
display of an amplitude strength of the CS respiration are
performed, i.e., consisting of hypopneas versus apneas.
[0047] According to the invention, an ascertainment is performed of
a trend of the amplitude strength over hours or days or weeks as an
indicator for change of an illness, for example, cardiac
insufficiency or neurological illness.
[0048] According to the invention, the recognized CS respiration is
confirmed or discarded by analysis of pulse oximeter signals.
Cyclic variation of SpO2 or the pulse frequency or the pulse wave
amplitude or the pulse transit time (PTT) are used as pulse
oximeter signals. The pulse oximeter is connected in this case via
an interface to the respiration device, to be able to record the
data in a time-correlated manner.
[0049] According to the invention, storage and display of the
ascertained period duration are performed.
[0050] According to the invention, the ascertainment of a trend of
the period duration is performed over hours or days or weeks, since
the period duration is an indicator of change of an illness, for
example, cardiac insufficiency or neurological illness.
[0051] The method according to the invention offers an
uncomplicated possibility for reliably recognizing CS respiration
during respiration by a respiration device. The method is
particularly preferably designed so that it is usable for operating
the respiration device according to the invention and the
refinements thereof. The method can thus be implemented
particularly well and the advantages thereof can be used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0052] Further advantages and features of the present invention
result from the description of the exemplary embodiment, which is
explained hereafter with reference to the appended Figures.
[0053] In the Figures:
[0054] FIG. 1 shows a respiration device according to the
invention; and
[0055] FIG. 2 shows an outlined event analysis.
DETAILED DESCRIPTION OF EMBODIMENTS
[0056] The particulars shown herein are by way of example and for
purposes of illustrative discussion of the embodiments of the
present invention only and are presented in the cause of providing
what is believed to be the most useful and readily understood
description of the principles and conceptual aspects of the present
invention. In this regard, no attempt is made to show details of
the present invention in more detail than is necessary for the
fundamental understanding of the present invention, the description
in combination with the drawings making apparent to those of skill
in the art how the several forms of the present invention may be
embodied in practice.
[0057] FIG. 1 shows a respiration device 1 according to the
invention in a perspective illustration. The respiration device 1
is a home respiration device in particular. The respiration device
1 is provided and designed for operation according to the method
according to the invention.
[0058] The respiration device 1 comprises a respiration unit 2,
which is enclosed by a housing 101, having a fan unit 3 for
generating an airflow for respiration. A monitoring unit 5 having a
storage unit 15, a controller 25, and a sensor unit 35 is provided
for controlling the respiration unit 2.
[0059] The operation and setting of the respiration device 1 are
performed via an operating unit 7 having a display unit 17 and an
interface for the data exchange 27. A humidifier unit 6 is provided
for increasing the moisture content of the breathing air.
[0060] The respiration device 1 has a breathing interface 4 to
supply the airflow to a user for respiration. The breathing
interface is preferably designed as a patient interface, which is
typical in the case of respiration devices, and can be embodied,
for example, as a full face mask or as a nasal pillow or as a tube
or as a larynx mask. The breathing interface 4 shown here is a
breathing mask 14 designed as a nasal mask. Headgear 24 is provided
for fixing the breathing mask 14.
[0061] A connection hose 54, which is connected by means of a
coupling unit 64 to the respiration unit 2, is provided for
connecting the breathing interface 4 to the respiration unit 2. The
connection hose 54 is connected to the breathing interface 4 via a
coupling element 34. An expiration element 44, which comprises a
valve or is designed as a valve, is arranged between the connection
hose 54 and the coupling element 12. The expiration element 44 is
provided in particular to prevent breathing out into the
respiration device 1 during the expiration of the user.
[0062] The monitoring unit 5 is operationally connected to the
sensor unit 35, which has one or more sensors for detecting
variables which are characteristic for the respiration parameter.
For example, the sensor unit 35 has a pressure sensor (not shown
here), which detects the pressure conditions in the region of the
breathing interface. For this purpose, the pressure sensor has a
flow connection via a pressure measurement hose 350 to the
breathing interface 4.
[0063] The pressure measurement hose 350 extends in this case from
the breathing interface 4 along the connection hose 54 to an intake
nozzle 351 on the housing 101. The pressure measurement hose 350
has a flow connection to the pressure sensor of the sensor unit 35
via the intake nozzle 351.
[0064] The flow measurement is performed in this case via a
throttle, which is arranged in the main channel of the flow
connection between fan unit 3 and breathing interface 4. An
arrangement in a secondary channel is also possible. To be able to
monitor further respiration parameters, the sensor unit 35 can also
be equipped with sensors for measuring the respiratory excursion,
for measuring an oxygen saturation of the blood, and/or for
measuring EEG, EMG, EOG, or EKG activity.
[0065] Furthermore, the monitoring unit 5 has a controller 25 for
activating the fan unit 3. The controller 25 provides a required
minimum pressure and compensates for pressure variations which are
caused by the respiration activity of the user. For example, the
controller 25 also detects the current pressure in the breathing
mask 14 and adjusts the output of the fan unit 3 accordingly, until
a desired respiration pressure is applied.
[0066] The respiration device 1 shown here can be designed as a
fixed level device or also as an automatic level device. In
particular, regulation to setpoint values, which were previously
calculated individually and fixed on the basis of the
characteristic respiration of a user, is performed in this case by
the monitoring unit 5.
[0067] It is also possible that the respiration unit 2 is adapted
dynamically and in particular according to the respiration phase of
the user. For example, a respiration phase change can be recognized
on the basis of the monitoring unit 5, so that a higher or lower
pressure can be provided depending on the respiration phase. For
example, the respiration device 1 can be designed as a CPAP or APAP
device. The respiration device 1 can also be designed as a bilevel
device. For example, the respiration device 1 reacts to specific
respiration events, for example, snoring, shallow breathing, and/or
obstructive pressure spikes, with corresponding settings of the
respiration parameters.
[0068] Using the respiration device 1 shown here, events which
occur in the respiration or during the respiration are recognized
and classified. For this purpose, the sensor unit 35 detects one or
more respiration parameters and supplies corresponding signals to
the monitoring unit 5, for example, a flow signal and/or a pressure
signal. The monitoring unit 5 analyzes the signals by means of
suitable algorithms, so that characteristic signal curves can be
recognized and classified as an event. In this case, for example, a
parameter extraction can be used with respect to level and
amplitude values, time intervals, envelopes, zero crossings, and
slopes. During an analysis with regard to time features, for
example, periodicities and frequencies are used in a parameter
extraction.
[0069] The recognized events can then be stored in the storage unit
15 and used for a respiration statistic. One advantage of the event
recognition is that an adaptation of the respiration can be
performed based on the classified events, for example, an automatic
pressure increase in the event of obstructive apnea. In addition, a
diagnosis of specific respiratory disturbances can be performed to
a certain extent.
[0070] A particular advantage of the respiration device 1 shown
here is the monitoring unit 5, which further analyzes the
recognized events and registers CS respiration on the basis of a
characteristic occurrence of the events. Such an event analysis 8
is outlined as an example in FIG. 2.
[0071] FIG. 2 shows five exemplary events 19, 29, 39, 49, 59, which
were detected and classified during a time 10. The first and the
second and also the third event 19, 29, 39 each correspond here to
a central apnea occurring in the respiration. The fourth event 49
corresponds to an obstructive apnea. The fifth event 59 stands here
for a snore occurring during the respiration. Further events (not
shown here) can have occurred and can have been detected between
the individual events 19, 29, 39, 49, 59, for example, a
hyperventilation.
[0072] For the event analysis 8, the monitoring unit 5 firstly
sorts the events according to their relevance with respect to CS
respiration. In this case, for example, a central hypopnea and a
central apnea are relevant. The monitoring unit 5 therefore
classifies the first, second, third, and fourth events as relevant
for CS recognition and sorts them, for example, into a first
relevance class. The fifth event 59, which is classified as a
snore, is considered to be irrelevant for the CS recognition and is
sorted by the monitoring unit 5, for example, into a second
relevance class. For the further event analysis 8, the monitoring
unit 5 then only still considers the events of the first relevance
class.
[0073] Subsequently, the monitoring unit 5 analyzes the occurrence
of the relevant events over the time 10. For this purpose, the
monitoring unit 5 ascertains the moment of the start S, the moment
of the end E, and the chronological middle of each of the relevant
events. Subsequently, the period lengths are determined, which each
extend from the middle M of one event to the chronological middle M
of the subsequent event. A first period length 18 thus results
between the first and second events 19, 29, a second period length
28 results between the second and third events 29, 39, and a third
period length 38 results between the third and fourth events 39,
49.
[0074] In a next step, the monitoring unit 5 compares the first
period length 18 to the second period length 28. If the comparison
results in a maximum deviation of 30% of the period lengths 18, 28
from one another, it is registered as an indication of CS
respiration. Subsequently, the deviation between the second period
length 28 and the third period length 38 is also ascertained and,
in the event of a maximum deviation of 30%, is evaluated as a
further indication of the presence of CS respiration. In this case,
still more than four events can also be analyzed and taken into
consideration for the event analysis 8, so that the comparison also
extends over further adjacent period lengths.
[0075] The monitoring unit 5 uses the respective value of the
period length between the events as a further indication of the
presence of CS respiration. In this case, the presence of CS
respiration is presumed when the period lengths are each at least
40 seconds and at most 90 seconds.
[0076] Subsequently, the monitoring unit 5 checks the ratio between
the chronological duration of one event and the associated period
length. For example, the duration of the first event 19 from the
start S to the end E is ascertained and compared to the first
period length 18. The monitoring unit 5 registers an indication of
CS respiration in this case when the chronological duration is at
most 70% of the associated period length. The chronological
duration of the second and third events 29, 39 is accordingly
compared to the respective associated period length 28, 38 and
analyzed.
[0077] Subsequently, the events sorted as relevant are validated by
the monitoring unit 5. In this case, events are classified as valid
when they typically occur during CS respiration. The events are
classified as invalid which typically do not occur during CS
respiration or the single or multiple occurrence of which negates
CS respiration. For example, a central apnea or hypopnea are
considered to be valid events. An obstructive apnea or hypopnea are
considered to be invalid, for example.
[0078] In this case, the monitoring unit 5 sorts the events into a
first validity class and a second validity class. The first
validity class comprises here the first, second, and third events
19, 29, 39, which were each classified as apnea. The fourth event
49, which was classified as obstructive hypopnea, is sorted into
the second validity class.
[0079] Subsequently, the monitoring unit 5 considers the number of
the events sorted into the first and the second validity classes
together with the total number of all events considered in the
event analysis in the sense of a conclusiveness test. In the
example shown here having four relevant events, the presence of CS
respiration is assumed if, of three events, at least two are
classified as valid events and at most one is classified as an
invalid event.
[0080] The differentiation between a central apnea, which can be
classified as a valid event, and an invalid obstructive apnea is
preferably executed by the monitoring unit 5 on the basis of an
analysis of the flow signal and the pressure signal. The signals
are tapped between the breathing interface 4 and the expiration
element 44. The beginning of an apnea is recognized on the basis of
a flow variation and the end of the apnea is recognized on the
basis of a pressure variation.
[0081] The end of the apnea can also be recognized by the
occurrence of a pressure variation or flow variation, however. The
delimitation of an obstructive apnea is performed in this case by
the occurrence of a short, additional pressure increase at the end
of the apnea. To delimit the pressure increase from possible
artifacts, for example, movements or heartbeat of the user, a
corresponding limiting value can be defined. In addition, the
pressure increase is so short that it is substantially shorter than
typical respiration periods and therefore can be delimited
therefrom.
[0082] The event analysis 8 is preferably performed in
consideration of agreements on the recognition of respiratory
disturbances. For example, the AASM manual describes corresponding
rules for event recognition and classification, which are to be
taken into consideration during the analysis. The monitoring unit 5
is in particular able and designed to consider these rules during
the event analysis for recognizing the CS respiration in a
corresponding manner. Corresponding queries and/or algorithms are
stored in the monitoring unit 5.
[0083] For example, to recognize CS respiration, at least five
central apneas and/or central hypopneas per hour during the sleep
of the user must occur in conjunction with the typical pattern of
an increase and flattening of the respiration over at least two
hours of observation time. In addition, it is possible that central
apneas which occurred during already recognized CS respiration are
considered as individual apneas and incorporated accordingly in the
event analysis 8.
[0084] If the event analysis 8 has the result that CS respiration
is present, this can be stored on the basis of a corresponding
entry in a respiration statistic. The user can retrieve the
respiration statistic, for example, via the interface 27 and use it
to judge the respiration therapy. Depending on the frequency of the
CS respiration, a manual or program-assisted changeover of the
respective respiration parameters can then also be performed. The
monitoring unit 5 can, in the event of an occurrence of CS
respiration, also perform an automatic adaptation of the
respiration unit 2 and recalculate corresponding setpoint values
for respiration parameters. For example, a specific therapy mode
can be set, which the CS respiration provides by anti-cyclic
regulation of the compression stroke.
[0085] While the present invention has been described with
reference to exemplary embodiments, it is understood that the words
which have been used herein are words of description and
illustration, rather than words of limitation. Changes may be made,
within the purview of the appended claims, as presently stated and
as amended, without departing from the scope and spirit of the
present invention in its aspects. Although the present invention
has been described herein with reference to particular means,
materials and embodiments, the present invention is not intended to
be limited to the particulars disclosed herein; rather, the present
invention extends to all functionally equivalent structures,
methods and uses, such as are within the scope of the appended
claims.
[0086] To sum up, the present invention provides:
[0087] 1. A respiration device, wherein the device comprises at
least one respiration unit for generating an airflow for
respiration and at least one monitoring unit for detecting at least
one respiration parameter and for classifying events in the
respiration on the basis of monitoring of the respiration
parameter, the monitoring unit being able and designed to carry out
at least one event analysis to recognize an occurrence of
chronologically successive events which is characteristic for
Cheyne-Stokes respiration and for this purpose to ascertain period
lengths between the chronologically successive events and to
compare the ascertained period lengths at least partially to one
another and to register the presence of Cheyne-Stokes respiration
when the compared period lengths deviate by less than 40% from one
another.
[0088] 2. The respiration device according to item 1, wherein the
monitoring unit is able and designed to carry out at least one
event analysis for recognizing an occurrence of at least three
chronologically successive events which is characteristic for
Cheyne-Stokes respiration and for this purpose to ascertain at
least one first period length between a first event and a second
event and one second period length between a second event and a
third event and to at least partially compare them to one another
and to register the presence of Cheyne-Stokes respiration when the
first period length and the second period length deviate from one
another by less than 40%.
[0089] 3. The respiration device according to any one of items 1
and 2, wherein the monitoring unit is able and designed to carry
out at least one event analysis for recognizing an occurrence of at
least four chronologically successive events which is
characteristic for Cheyne-Stokes respiration and for this purpose
to ascertain at least one first period length between a first event
and a second event and one second period length between a second
event and a third event and one third period length between a third
event and a fourth event and to at least partially compare them to
one another and to register the presence of Cheyne-Stokes
respiration when the first period length and the second period
length and also the second period length and the third period
length each deviate by less than 40% from one another.
[0090] 4. The respiration device according to item 3, wherein the
monitoring unit is able and designed to register the presence of
Cheyne-Stokes respiration when the first period length and the
second period length and also the second period length and the
third period length each deviate by less than 35% and in particular
by less than 30% from one another.
[0091] 5. The respiration device according to any one of the
preceding items, wherein the period lengths extend between a
chronological middle of one event and a chronological middle of a
following event.
[0092] 6. The respiration device according to any one of the
preceding items, wherein the monitoring unit is able and designed
to sort the events into at least two relevance classes, comprising
at least one first relevance class having events which are relevant
for Cheyne-Stokes respiration and at least one second relevance
class having events which are irrelevant for Cheyne-Stokes
respiration.
[0093] 7. The respiration device according to item 6, wherein the
first relevance class comprises at least the events of a
hyperventilation and/or a hypoventilation and/or a hypopnea and/or
an apnea and/or the second relevance class comprises at least the
events of inspiration, expiration, snoring, swallowing, speaking,
nose blowing, and/or coughing, and/or a respiration interruption
and/or a leak.
[0094] 8. The respiration device according to any one of items 5 to
7, wherein the monitoring unit is able and designed to sort the
events of the first relevance class into at least two validity
classes for the event analysis, comprising a first validity class
having events which typically occur in the case of Cheyne-Stokes
respiration and a second validity class having events which
typically do not occur in the case of Cheyne-Stokes
respiration.
[0095] 9. The respiration device according to any one of items 5 to
8, wherein the first validity class comprises at least the events
of a central apnea and/or a central hypopnea and/or the second
validity class comprises at least the events of an obstructive
apnea and/or an obstructive hypopnea.
[0096] 10. The respiration device according to any one of items 7
to 9, wherein the monitoring unit is able and designed to register
the presence of Cheyne-Stokes respiration when at least three
events occur in chronological succession and in this case at least
two of the at least three events correspond to the first validity
class and at most one event of the at least three events
corresponds to the second validity class.
[0097] 11. The respiration device according to any one of the
preceding items, wherein the monitoring unit is able and designed
to register the presence of Cheyne-Stokes respiration when a first
and a second and a third period length are each at least 35 seconds
and at most 95 seconds.
[0098] 12. The respiration device according to any one of the
preceding items, wherein the monitoring unit is able and designed
to register the presence of Cheyne-Stokes respiration when a
chronological duration of each one of the events taken into
consideration for the event analysis is at most 80% and in
particular at most 70% of the period length.
[0099] 13. The respiration device according to any one of the
preceding items, wherein the monitoring unit is able and designed
to monitor at least one flow signal and/or at least one pressure
signal from at least one associated sensor unit to detect at least
one flow property and/or at least one pressure property of the
airflow for the respiration and to analyze it on the basis of at
least one algorithm, in order to classify an event.
[0100] 14. The respiration device according to any one of the
preceding items, wherein the monitoring unit is able and designed
to output a corresponding notification to a user in the event of
registered Cheyne-Stokes respiration and/or to consider it as a
corresponding respiratory disturbance in a respiration statistic.
15. A method for operating a respiration device comprising at least
one respiration unit for generating an airflow for respiration and
at least one monitoring unit for detecting at least one respiration
parameter and for classifying events in the respiration on the
basis of monitoring of the respiration parameter, wherein, on the
basis of at least one event analysis, at least one occurrence of
chronologically successive events is recognized, which is
characteristic for Cheyne-Stokes respiration, and for the event
analysis, period lengths are ascertained between the
chronologically successive events and at least partially compared
to one another, and the presence of Cheyne-Stokes respiration is
registered when the compared period lengths deviate from one
another by less than 40%.
LIST OF REFERENCE NUMBERS
[0101] 1 respiration device
[0102] 2 respiration unit
[0103] 3 fan unit
[0104] 4 breathing interface
[0105] 5 monitoring unit
[0106] 6 humidifier unit
[0107] 7 operating unit
[0108] 8 event analysis
[0109] 10 time
[0110] 14 breathing mask
[0111] 15 storage unit
[0112] 17 display unit
[0113] 18 period length
[0114] 19 event
[0115] 24 headgear
[0116] 25 controller
[0117] 27 interface
[0118] 28 period length
[0119] 29 event
[0120] 34 coupling element
[0121] 35 sensor unit
[0122] 38 period length
[0123] 39 event
[0124] 44 expiration element
[0125] 49 event
[0126] 54 connection hose
[0127] 59 event
[0128] 64 coupling unit
[0129] 101 housing
[0130] 350 pressure measurement hose
[0131] 351 intake nozzle
* * * * *